scholarly journals Visual modelling suggests a weak relationship between the evolution of ultraviolet vision and plumage coloration in birds

2015 ◽  
Vol 28 (3) ◽  
pp. 715-722 ◽  
Author(s):  
O. Lind ◽  
K. Delhey
Keyword(s):  
Plumage Coloration ◽  
Weak Relationship ◽  
Ultraviolet Vision

scholarly journals Multiple shifts between violet and ultraviolet vision in a family of passerine birds with associated changes in plumage coloration

2011 ◽  
Vol 279 (1732) ◽  
pp. 1269-1276 ◽  
Author(s):  
Anders Ödeen ◽  
Stephen Pruett-Jones ◽  
Amy C. Driskell ◽  
Jessica K. Armenta ◽  
Olle Håstad
Keyword(s):  
Plumage Coloration ◽  
Amino Acid Residues ◽  
Avian Evolution ◽  
Phylogenetic Reconstructions ◽  
Single Cone ◽  
Male Plumage ◽  
Ultraviolet Vision ◽  
Character Correlation ◽  
Cone Opsins

Colour vision in diurnal birds falls into two discrete classes, signified by the spectral sensitivity of the violet- (VS) or ultraviolet-sensitive (UVS) short wavelength-sensitive type 1 (SWS1) single cone. Shifts between sensitivity classes are rare; three or four are believed to have happened in the course of avian evolution, one forming UVS higher passerines. Such shifts probably affect the expression of shortwave-dominated plumage signals. We have used genomic DNA sequencing to determine VS or UVS affinity in fairy-wrens and allies, Maluridae, a large passerine family basal to the known UVS taxa. We have also spectrophotometrically analysed male plumage coloration as perceived by the VS and UVS vision systems. Contrary to any other investigated avian genus, Malurus (fairy-wrens) contains species with amino acid residues typical of either VS or UVS cone opsins. Three bowerbird species (Ptilonorhynchidae) sequenced for outgroup comparison carry VS opsin genes. Phylogenetic reconstructions render one UVS gain followed by one or more losses as the most plausible evolutionary scenario. The evolution of avian ultraviolet sensitivity is hence more complex, as a single shift no longer explains its distribution in Passeriformes. Character correlation analysis proposes that UVS vision is associated with shortwave-reflecting plumage, which is widespread in Maluridae.

Use of the TOEFL as a Standard for University Admission: A Position Statement by the Canadian Psychological Association

1998 ◽  
Vol 14 (3) ◽  
pp. 261-265 ◽  
Author(s):  
Marvin L. Simner
Keyword(s):  
Academic Achievement ◽  
Foreign Language ◽  
Position Statement ◽  
Considerable Evidence ◽  
Canadian Universities ◽  
Weak Relationship ◽  
University Admission ◽  
Canadian Psychological Association

Nearly all Canadian universities employ, as a standard for university admission, the Test of English as a Foreign Language (TOEFL). In light of considerable evidence indicating only a weak relationship between TOEFL scores and academic achievement, the Canadian Psychological Association recently issued a report containing a position statement that called upon Canadian universities to refrain from employing the TOEFL in this manner. Because the concerns raised in the report are likely to apply to many universities outside Canada, the entire report is reproduced in this article.

scholarly journals Feather corticosterone levels are not correlated with health or plumage coloration in juvenile house finches

2018 ◽  
Vol 124 (2) ◽  
pp. 157-164 ◽  
Author(s):  
Tuul Sepp ◽  
Steve Desaivre ◽  
Adam Z Lendvai ◽  
József Németh ◽  
Kevin J McGraw ◽  
...  
Keyword(s):  
Plumage Coloration ◽  
House Finches ◽  
Feather Corticosterone

scholarly journals Ultraviolet vision in larval Neogonodactylus oerstedii

2022 ◽  
Author(s):  
Marisa S. McDonald ◽  
Sitara Palecanda ◽  
Jonathan H. Cohen ◽  
Megan L. Porter
Keyword(s):  
Visual Pigment ◽  
Molecular Diversity ◽  
Animal Kingdom ◽  
Uv Sensitivity ◽  
Color Detection ◽  
Uv Vision ◽  
Ultraviolet Vision ◽  
The Caribbean ◽  
Different Color ◽  
Spectral Channels

Stomatopod crustaceans have among the most complex eyes in the animal kingdom, with up to twelve different color detection channels. The capabilities of these unique eyes include photoreception of ultraviolet (UV) wavelengths (<400 nm). UV vision has been well characterized in adult stomatopods but has not been previously demonstrated in the comparatively simpler larval eye. Larval stomatopod eyes are developmentally distinct from their adult counterpart and have been described as lacking the visual pigment diversity and morphological specializations found in adult eyes. However, recent studies have provided evidence that larval stomatopod eyes are more complex than previously thought and warrant closer investigation. Using electroretinogram recordings in live animals we found physiological evidence of blue and UV sensitive photoreceptors in larvae of the Caribbean stomatopod species Neogonodactylus oerstedii. Transcriptomes of individual larvae were used to identify the expression of three distinct UV opsins transcripts, which may indicate the presence of multiple UV spectral channels. This is the first paper to document UV vision in any larval stomatopod, expanding our understanding of the importance of UV sensitivity in plankton. Similar to adults, larval stomatopod eyes are more complex than expected and contain previously uncharacterized molecular diversity and physiological functions.

scholarly journals PengaruhUtangdan PerputaranModalKerjaTerhadapProfitabilitasPerusahaan(Studi Kasus Pada PT Bumi Sekar Tbk Periode 2013-2018)

2020 ◽  
Vol 15 (1) ◽  
pp. 32
Author(s):  
Saprudin ◽  
Bayu Hartono
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Quantitative Research ◽  
Linear Regression Analysis ◽  
Strong Relationship ◽  
Financial Statements ◽  
Working Capital ◽  
Weak Relationship ◽  
Spss Software ◽  
Relationship Of

This study aims to determine how much influence the debt, working capital turnover has on the profitability of PT Sekar Bumi Tbk. Debt is proxied by DER, working capital turnover is proxied by WCT, while profitability is proxied by ROA. Based on the nature of the data used in this study is a type of quantitative research. Samples were taken, namely PT Sekar Bumi Tbk with the objectof research of 2013-2018 financial statements. Linear regression analysis was used in this study, with the help of SPSS software for Windows 20.0. The results of this study explain that partially DER has a significant effect on ROA, and has a very strong relationship of 83.9%. WCT has no significant effect on ROA, and has a very weak relationship of 18.4%. However, simultaneously DER and WCT has a significant effect with a contribution of 70.8% to ROA. So companies need to pay attention and consider how much effective the use of debt as a source of funding for the company.

Otolith and fish size relationships, measurement error, and size-selective mortality during the early life of Atlantic salmon (Salmo salar)

1998 ◽  
Vol 55 (7) ◽  
pp. 1663-1673 ◽  
Author(s):  
M G Meekan ◽  
J J Dodson ◽  
S P Good ◽  
DAJ Ryan
Keyword(s):  
Measurement Error ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Data Sets ◽  
Regression Analyses ◽  
Fish Size ◽  
Atlantic Salmon Salmo Salar ◽  
Weak Relationship ◽  
Growth Increments ◽  
Otolith Size

The development of the relationship between otolith and body size in Atlantic salmon (Salmo salar) between hatching and emergence was examined by repeatedly measuring individually identified fish. Otolith growth increments were deposited daily in the period between hatching and emergence. Comparison of back-calculated otolith size and standard length using least squares regression analyses revealed a weak relationship between these variables at each of the 5-day sampling intervals. However, when data sets were pooled among intervals, variation in otolith size accounted for 98% of the variation in alevin length. A computer simulation demonstrated that levels of measurement error similar to those documented in our study resulted in the failure of regression analyses to detect strong relationships between otolith and fish size. Mortality that occurred during the experiment was strongly size selective. This truncated the size ranges of fish in cross-sectional data sets and thus reduced the ability of regression analysis to detect relationships between otolith and fish size. We propose that the weak relationship between otolith and fish size at emergence recorded in previous studies was an artifact of measurement error and the truncation of size ranges in regression analyses. Differences in alevin size at emergence were present at hatching and had been propagated by growth.

Geography and age are related to plumage coloration of male Golden-winged Warblers (Vermivora chrysoptera)

2018 ◽  
Vol 130 (1) ◽  
pp. 286-296
Author(s):  
Anna C. Tisdale ◽  
John Anthony Jones ◽  
Kyle R. Aldinger ◽  
Marja H. Bakermans ◽  
Jeffery L. Larkin ◽  
...  
Keyword(s):  
Plumage Coloration ◽  
Vermivora Chrysoptera
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